72 FOEEST PLANTING. 



the drawers of the lowest tier. When the cones beneath 

 have opened as extensively as possible they are taken 

 out and placed in a churn-like vessel with an opening, by 

 which the seeds which have remained in the cones may 

 pass, and be received in a wooden box placed beneath. 

 The cones are then well shaken until completely emptied 

 of their seeds, and the empty cones are employed to feed 

 the fire in the furnace. 



At some places in Germany they use, instead of 

 these hot houses, ovens with iron plates on the tops, 

 upon which the cones are placed, and by heat forced to 

 discharge the seeds. This device is not to be recom- 

 mended, as the plates very often become too hot, and the 

 seeds are burnt and deprived of their vitality. 



The extraction of seeds by solar heat is preferable to 

 that by artificial heat, as the seeds thus obtained, never 

 having been exposed to excessive heat, do not lose their 

 vitality. When solar heat is to be employed, a frame- 

 work or scaffolding similar to that just before described 

 is placed against the wall of a building on a southern ex- 

 posure. Upon this the trays are arranged of such a 

 height between that the sun's rays may fall on all alike. 

 Under the lowest trays are drawers provided with cover- 

 ings of thick cloth, so that, if rain falls, the seed may be 

 covered at once and kept dry. The whole apparatus is 

 covered with a light roof, the slope of which runs toward 

 the north. After the cones have been exposed for some 

 time to the sun and summer heat they will open, and 

 then they should be shaken, commencing with the trays 

 in the upper tiers and proceeding in regular succession 

 to those of the lowest row, whereupon the seeds are col- 

 lected in the drawer. When the cones have opened as 

 much as possible they are taken away and put in a churn, 

 such as has been described above, for the extraction of 

 the seeds which have remained in the cones. 



If it is desired to divest the seeds of their wings, the 



